CODEWITHSUNDEEP
javascriptarraysobject
Per Arne Andersen
Per Arne Andersen

Reputation: 544

Retrieve Path of Object items

I'm wondering if its possible to retrieve all paths a javascript object contains

Example:

obj = {
  prop1 : {
    x: 19
    y: 43
  }
  prop2 : {
    another: {
      here: 1
    }
  }
  prop3: "hello"
}

Where the result would be an array with following elements:

Result: ["prop1.x", "prop1.y", "prop2.another.here", "prop3"]

Is this possible?

Thanks!

Upvotes: 1

Views: 111

Answers (2)

Josh from Qaribou
Josh from Qaribou

Reputation: 6908

Wrote this while Tomalak was putting together here. Recursion's the obvious approach for doing this.

var inputObject = {
    prop1: {
        x: 19,
        y: 43
    },
    prop2: {
        another: {
            here: 1
        }
    },
    prop3: "hello"
};

function getProps(obj) {
  var props = [];

  var findPropsRecursive = function (robj, str) {
    robj = robj || {};
    var keys = Object.keys(robj);
    if (keys.length > 0 && (robj instanceof Object)) {
      return keys.map(function (key) {
        return findPropsRecursive(robj[key], str + (str ? '.' : '') + key);
      });
    } else {
      props.push(str);
      return '';
    }
  };

  findPropsRecursive(obj, '');

  return props;
}

console.log(getProps(inputObject));

on jsfiddle: http://jsfiddle.net/jkoudys/w49rcp40/

Upvotes: 2

Tomalak
Tomalak

Reputation: 338406

function flattenKeys(obj, delimiter) {
    delimiter = delimiter || '.';

    return recurse(obj, '', []);

    function recurse(obj, path, result) {
        if (typeof obj === "object") {
            Object.keys(obj).forEach(function (key) {
                recurse(obj[key], path + delimiter + key, result);
            });
        } else {
            result.push(path.slice(delimiter.length));
        }
        return result;
    }
}

used as

var obj = {
  prop1 : {
    x: 19,
    y: 43
  },
  prop2 : {
    another: {
      here: 1
    }
  },
  prop3: "hello"
};

flattenKeys(obj);

// -> ["prop1.x", "prop1.y", "prop2.another.here", "prop3"]

Alternative implementation without string operations:

function flattenKeys(obj, delimiter) {
    delimiter = delimiter || '.';

    return recurse(obj, [], []);

    function recurse(obj, path, result) {
        if (typeof obj === "object") {
            Object.keys(obj).forEach(function (key) {
                path.push(key);
                recurse(obj[key], path, result);
                path.pop();
            });
        } else {
            result.push(path.join(delimiter));
        }
        return result;
    }
}

Upvotes: 3

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